Furnace construction



' June l, 1931 F. z. AHL l,810,457

FURNACE CONSTRUCTION Eiled June 6, 1927 2 Sheets-Sheet l 26 ff f "y l E i Z5 A TTORNEYS.

June 16, 1931. F. z. AHL 1,810,457

",FRNACE CONS TRUCTI ON Filed June 6, 1927 2 Sheets-Sheet 2 maid/2%@ f A TTORNEYS.

Patented June 16, 1931" v UNIT ED; sifle'res'y PATENTOFFICB FRANK Z. AHL, OF, SACRAMENTO, CALIFORNIA FURNACE CONSTRUC'I'ION Application mea vJune e,

furnaces with linings which resist the action f ofcombustion within'the hre-box of the furnace, and which maintain their sha e irrespective of the temperature created y com- 10 bustion.; In'most Vinstances these linings are of such design. and construction'v asto make them diliicult to prepare and to maintain in the condition which will prevent them from overheating.;rv It is the principal object of the '15 present invention, therefore, to provide a furnace structure in which a peculiar type of segmental interlocking lining of metal is provided, which lining is rsubstantially self-supporting in its assembled position, vthus creaty y220 ing anair space between the side wall ofthe fire-box vandy the lining Ywhereby additional air to support the combustion of otherwise unburnedgases may be provided, and whereby the lining willbe maintained at such a '25 temperature' as to'vprevent it rfrom being burned away.r Y f y The present invention contemplates the use of a furnace having the usual air jacket within which is disposed a fire-box, which y fire-box is lined by'a plurality of interlock-f ing lining members.- n

The Vinvention `is' illustrated Vby way of example inv the. 'accompanying drawings, in which: K

Eig. -1 isa view: in central',vertical section through the furnace,l showing thek structure with which the present invention isl con@ cerne'd.` j c l c Fig. 2 1s an enlarged view in perspective,

i k10 showingl the lining of the furnacewith parts brokenaway for the sake of clearness.

i V1f`ig.' is ancenl'arged view in perspective showing ya lining member as used along one side ofthe feeddoor.

' 45 Fig, 4' is a view in perspective showing'one `details of' one of the lining members.

1927. Serial No. 196,675.

of the lining members used in the body of the lirey boX. Y-

Fig.' 5 is anl enlarged fview in perspective showingone of the lining `members forming the bottom ofthe fee'd'door.` `V

Fig.y 6 is a viewin kperspective showing a formvof grate which l employ in connection l with my invention. f

Fig. 7 'is a view in perspective.- showing the 55 Referring more particularly to the drawings, 10 indicatesthe cylindrical air jacket of thepfurnace.y This jacket isitted at yits upper yend with ay dome 11 to which is connected a plurality of hotvairconduits V12. 60, The lower end ofthe cylindricaljacket 10 is closed by a bottom member 13.j Disposed within the cylindrical air jacket structure 'is a fire-box 14.' This lire-box ishere shown as also being `cylindrical-*in shape and as be 165 ing of such a diameter as to create an air circulating spiace between the outer shell 10 and the shell of the ireboxy The lower end of the fire-box is formed with an outletopenopening 19 communicating with .afiring door passageway 20. This passageway extends lthrough an opening in the outer sidewall l() of the furnace, the passageway and open- B5 ingfbeingv normally closed by` a firing ,door

21. At the opposite side of thelire-box wall is an outlet opening 22 in communication with a flue chamber 23 and a iiueplpe .24. ,It is understood that products of combustion ce from the fire-box may pass outwardly through the opening 22 to the flue 24.

It may be found desirable to burn wood, coal or oil in the furnace, in which event various rearrangements of the grate structure 52 may be necessary. When wood or coal is to be burned, the grate 54 may be placed upon a grate ring 25. Any type of grate may be used in place of the one indicated in Fig. 6 of the drawings. In any event it is essential that the fire-box shall be lined to prevent oxidation ofthe metal side walls of the fire-box. This is done in the present instance by providing the lining 26, which comprises a plurality of interlocking segments supported upon the grate ring 25. The grate ring is carried upon flanged members 27, secured to the inner faces of the fire-box side Wall. This grate ring is formed with an annular center portion 28 terminating at its lower end in an inturned supporting flange 29, and at a point near its upper end in a horizontally projecting annular flange 30. Circumscribing annular ribs 31 are carried upon the flange and spaced a distance therefrom yto provide an annular groove 32, into which the lips along the lower edges of the segmental lining members may project. The lining members are vpreferably formed of metal. The lining is essentially construct-4 ed of a plurality of segments 33, as indicated particularly in Fig. 4 of the drawings, and the necessary door framing segments 34 and 35, as indicated in Figs. 3 and 5 ofthe drawings. ;The segments 33 comprise body portions 36, which` are arcuate in horizontal cross section and are of any desired vertical length. These body portions are formed along one edge and the lower end with flanges 37 and-38 respectively whichfoverhang the side and edge of the body portion 36. The opposite edge of the segment 33 from its edge 37, is formed with a flange 39 which is oppositely offset from the flange 37, and is complementary to 'the flange 37 of a contiguous lining segment 33 when the segments are assembled. The upper end of the flanges 39 on the lining segments 33 follow the con` tour of the end of the segments, and are recurved to terminate in a locking lug 40, which is substantially parallel to the flange 39 and is spaced a distance therefrom to form a mortise 41 substantially equal to the thickness of the flange 37and of such formation as to conform to the contour of the upper end of the. flange 37' of the contiguous lining segment 33 when the segments a-reassembled. It will be understood that when the lining is assembled the projecting flanges 38 of the lining sections will extend into the annular channel 32 occurring between the ribs 31 of thev grate ring. In order to fit the firing opening and to prevent the products of combustion yfrom seeping through the joints of the firing opening and into the air circulating chamber, it is desirable to make a neat and tight joint between the lining members and the firing opening. This is done in the present instance by use of lining sefrments 34 and 35. The segments 34 are lformed with flanges 42, which extend horizontallyk and meet the edges of the firing opening easting 20. The segment 34 is also provided with locking lugs upon each side, as is clearly shown in Fig, 3. As a result of this construction, it will be seen that it can be moved vertically out of engagement with the remaining segments and when so removed, the remaining segments can then be separated and removed one by one by a slight sidewise movement. The segments are formed with enlarged out-turned flanges 43 at their upper ends, which flanges abut against the side wall of the fire-box and rest upon small angle members v44 secured to the wall, as shown in Fig. .1 of the drawings. It will be evident that because of the provision of two locking lugsy upon the segment 34, no locking lug will be required upon the adjacent segment for the purpose of holding these two segments in lockedk engagement. Such a modified segment is shown in Fig. 7 of the drawing and is designated by the numeral 46. By this arrangement it `will be seen that when any section of the Vfire-box lining has become damaged it kmay be readilyk lifted out of its place and a new section substituted whereneeded by first removing the section 34, which may be termed a key section, and then removing the sections between it and the damaged section. It will further be evident that'by the use' of an interlocking and practically self-supporting lining it is possible to createan air passageway 45 between the side wall of the fire-box 14 and the lining 26, thus permitting a circulation of air to be created through the lower door of the furnace and upwardly along the passageway 45 and into thecombustion space in the top of the fire-box. It has been found that certain of the gases do not burn, due to .the fact that lthey Ado not have sufficient oxygen to support combustion, and that when air is supplied to the top of the fire-boxfin the manner here described, additional burning of combustible material will take place, thus making a hotter fire and at the Sametime keeping'y the fire-box in a relatively cool condition. It will also be evident that by creating a circulation of air between the lining and the metal side wall of the fire-box the side wall will be protected by rair insulation, which will prevent the high temperature of the lining from being transmitted to the wall of the lire-box.

While I khave shown the preferred `form of my invention, it is to be understood that various changes may be made in its construction by those skilled in theartwithout departing from the spirit'of the invention, as defined inthe appended claim.

Having thus described'my invention, what I Aclaim and desire-to secure by Letters Patent is A lire-box of the character described comprising a plurality of vertically extending cooperating sections, flanges formed on the vertical edges of said sections, and locking lugs carried bythe upper edges of said sections for maintainingthe flanges of adjacent sections in cooperative relation with each other.

FRANK Z. ALI-IL 

